I usually don't eat or drink on rides up to two hours. Usually I forget to bring the bottle. I just don't understand how some guys can drink so much on a ride. Note that this is the Pacific Northwest, where it is usually quite cool, and I'm riding in long-sleeve jersey and tights even on some summer days. Let's see, today I was on a three-hour ride. I took a half bottle of juice and a gel packet. I still had a quarter of the bottle left at the finish, and I had forgotten about the gel pack. It rained during the last hour and a half.
Afterwards, though, I had a sleeve of Dos Equis and a big enchilada/chili relleno/taco meal at the Mexican restaurant in Blaine! I guess I just save the eating and drinking for the end of the ride. Much more efficient, since your body is not spending energy digesting stuff while you ride. Oh, and I don't usually take stops. This is why my saddle has to be really comfortable. I think that when I did the 1,000 km brevet a few weeks ago, I was stopping maybe every 100 km or so (about 4 hours at a time on the bike).
Luis